The invention relates to a container with a film tube for receiving a flowable substance. Containers of this type are used as disposable packages for sealing and moulding compositions or other curable substances.
German Offenlegungsschrift No. 3,823,708 discloses containers for separately receiving pasty components which components can be dispensed and supplied to a mixer in an exactly defined volume ratio. Each component is contained in a rigid cartridge which is provided at its one end by a dispensing nozzle and closed at its other end by a movable piston.
The known container permits an exact metering of the components, but is relatively expensive and requires manufacturing with close tolerances to achieve a sufficient sealing of the piston. Moreover, when rigid cartridges are used as one-way containers, they constitute a disposal problem that is taken more and more seriously.
For these reasons, film tubes are nowadays preferred as one-way packages for flowable substances, which are placed in cylindrical chambers and cut open to have their contents pressed out. With such containers, only the film tube forms a disposable part which is inexpensive and requires only little space when empty. Containers of this type are described, for instance, in German Offenlegungsschrift No. 3,826,887, German Utility Model No. 8,901,554, and U.S. patent specification No. 3,838,796.
The known containers using film tubes, however, are disadvantageous in that the substance emerging from the tube is prone to contaminate the interior of the cylindrical chamber and after some time will impede the movement of the piston, thereby rendering the container inoperative. Because part of the substance will not pass through the dispensing nozzle but escape into the interior of the cylindrical chamber, no exact metering of the substance is possible. This is a serious disadvantage particularly with substances which form one component of a material that is to be mixed at an exact ratio.
To avoid these disadvantages, the German company Teroson uses a tube package for distributing its sealing materials, which has a ring externally adhered to one end of the tube. The ring is threaded for connection to a dispensing nozzle. The dispensing nozzle includes blades which during screwing cut an opening into the film tube within the ring. Upon cutting, it is necessary for the dispensing nozzle to be screwed off again to remove the cut-off piece of film, which would otherwise clog the dispensing nozzle. This handling is very cumbersome and dirty.
A similarly designed tube package, which is similarly awkward to handle, is known from German Offenlegungsschrift No. 3,500,625.